Rice ratooning cultivation is an imperative breakthrough technology for promoting supply-side structural reform of agriculture, implementing the national plan to reduce the area of double-cropping rice in the Yangtze ...Rice ratooning cultivation is an imperative breakthrough technology for promoting supply-side structural reform of agriculture, implementing the national plan to reduce the area of double-cropping rice in the Yangtze River basin, China. While, at the same time, it also contributes to ensure the absolute safety of grain ration and optimize grain production structure in China. Rice ratooning is a cropping system in which we take advantage of the regeneration characteristics of the rice plant. For instance, the axillary buds grow rapidly into seedlings and then proceed to the stage of tillering, heading, grain filling and ripening through adopting different planting measures after the main crop (the first cropping rice) is harvested. Ratoon rice has a long history dating back 1 700 years in China. Presently, two models are commonly employed for harvesting of ratoon rice, which are manual harvesting and mechanized harvesting of ratoon rice. However, with the migration of Chinese rural labor forces, mechanized technology for ratoon rice has now become the main planting and harvesting mode. Moreover, this is also the recommended cultivation technique with promising high grain yields and better economic efficiency and more importantly it has become increasingly popular due to its beneficial aspects with the ongoing efforts of scientific research. The grain yield for both the main crop and ratooning crop is usually 15 t ha^–1 yr^–1 with a significant improvement on the economic benefits compared to the middle season and double season rice, respectively.展开更多
De novo root regeneration(DNRR) has wide applications in agriculture such as those related to cutting technology. Detached Arabidopsis thaliana leaf explants can regenerate adventitious roots without added hormones. T...De novo root regeneration(DNRR) has wide applications in agriculture such as those related to cutting technology. Detached Arabidopsis thaliana leaf explants can regenerate adventitious roots without added hormones. The regenerative ability is highly dependent on the developmental status of the leaf. An immature leaf has a higher regenerative ability, while a mature leaf is difficult to regenerate. Using RNASeq analysis, we showed that the expression levels of many genes, including those in the auxin network,changed during leaf maturation. Particularly, the expression levels of many YUCCA(YUC) genes in the auxin biosynthesis pathway are responsive to leaf maturation. Overexpression of YUC1 in the yuc-1 D dominant mutant rescued the rooting defects caused by leaf maturation. In addition, YUC4 expression levels were also affected by circadian rhythms. The regenerative ability was reduced in both immature and mature mutant leaf explants from the new wuschel-related homeobox 11-3(wox11-3) and wox12-3 mutant alleles created by the CRISPR/Cas9 method. Overall, the transcriptome and genetic data, together with the auxin concentration analysis, indicate that the ability to upregulate auxin levels upon detachment may be reduced during leaf maturation. Thus, multiple developmental and environmental signals may converge to control auxin accumulation, which affects the efficiency of the WOX11/12-mediated DNRR from leaf explants.展开更多
文摘Rice ratooning cultivation is an imperative breakthrough technology for promoting supply-side structural reform of agriculture, implementing the national plan to reduce the area of double-cropping rice in the Yangtze River basin, China. While, at the same time, it also contributes to ensure the absolute safety of grain ration and optimize grain production structure in China. Rice ratooning is a cropping system in which we take advantage of the regeneration characteristics of the rice plant. For instance, the axillary buds grow rapidly into seedlings and then proceed to the stage of tillering, heading, grain filling and ripening through adopting different planting measures after the main crop (the first cropping rice) is harvested. Ratoon rice has a long history dating back 1 700 years in China. Presently, two models are commonly employed for harvesting of ratoon rice, which are manual harvesting and mechanized harvesting of ratoon rice. However, with the migration of Chinese rural labor forces, mechanized technology for ratoon rice has now become the main planting and harvesting mode. Moreover, this is also the recommended cultivation technique with promising high grain yields and better economic efficiency and more importantly it has become increasingly popular due to its beneficial aspects with the ongoing efforts of scientific research. The grain yield for both the main crop and ratooning crop is usually 15 t ha^–1 yr^–1 with a significant improvement on the economic benefits compared to the middle season and double season rice, respectively.
基金supported by grants from the National Natural Science Foundation of China (31630007, 31770399 and 21375066)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB27030103)+1 种基金the Key Research Program of CAS (QYZDB-SSWSMC010)the National Key Laboratory of Plant Molecular Genetics
文摘De novo root regeneration(DNRR) has wide applications in agriculture such as those related to cutting technology. Detached Arabidopsis thaliana leaf explants can regenerate adventitious roots without added hormones. The regenerative ability is highly dependent on the developmental status of the leaf. An immature leaf has a higher regenerative ability, while a mature leaf is difficult to regenerate. Using RNASeq analysis, we showed that the expression levels of many genes, including those in the auxin network,changed during leaf maturation. Particularly, the expression levels of many YUCCA(YUC) genes in the auxin biosynthesis pathway are responsive to leaf maturation. Overexpression of YUC1 in the yuc-1 D dominant mutant rescued the rooting defects caused by leaf maturation. In addition, YUC4 expression levels were also affected by circadian rhythms. The regenerative ability was reduced in both immature and mature mutant leaf explants from the new wuschel-related homeobox 11-3(wox11-3) and wox12-3 mutant alleles created by the CRISPR/Cas9 method. Overall, the transcriptome and genetic data, together with the auxin concentration analysis, indicate that the ability to upregulate auxin levels upon detachment may be reduced during leaf maturation. Thus, multiple developmental and environmental signals may converge to control auxin accumulation, which affects the efficiency of the WOX11/12-mediated DNRR from leaf explants.
